In a known tire manufacturing method, the tread of a tire and a base tire which provides the base for the tire are fabricated separately. Then the tread is placed on the outer periphery of the base tire through the medium of an uncured bonding rubber called a cushion rubber. Then the cushion rubber is cured, thereby integrating the tread and the base tire together with the bonding rubber as the bonding layer.
The rubber part forming the outer periphery of the base tire (hereinafter referred to as base rubber) has a significant influence on the rolling resistance of a product tire having the tread bonded thereon. Accordingly, the rubber material having excellent rolling resistance properties is used for the base rubber.
However, the rubber material providing superior rolling resistance performance tends to show reduced cut resistance (resistance to cuts in the rubber that can be caused by contact with other objects). Of particular concern therefore is the drops in cut resistance of the axial edges of the base tire. Thus, mini side rubbers made of rubber excelling in cut resistance are provided at the exposed edges of the base rubber. In this manner, the cut resistance is secured by covering and protecting the exposed edges of the base rubber.